Cash and Cash Equivalents and Advertising Accounting Policies, and Prior Year Reclassifications (Effect Of Reclassification Of Consolidated Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Accounts receivable and prepaid expenses	$ (5,874)	$ 4,045	$ (7,613)
Net cash provided by operating activities	148,380	160,261	149,076
Net increase (decreases) in cash and cash equivalents	(10,109)	1,099	(5,460)
Cash and cash equivalents at beginning of year	47,917	46,818	52,278
Cash and cash equivalents at end of period	37,808	47,917	46,818
As Previously Reported [Member]
Accounts receivable and prepaid expenses		9,598	(5,096)
Net cash provided by operating activities		165,814	151,593
Net increase (decreases) in cash and cash equivalents		6,652	(2,943)
Cash and cash equivalents at beginning of year	21,305	14,653	17,596
Cash and cash equivalents at end of period		21,305	14,653
Reclassifications [Member]
Accounts receivable and prepaid expenses		(5,553)	(2,517)
Net cash provided by operating activities		(5,553)	(2,517)
Net increase (decreases) in cash and cash equivalents		(5,553)	(2,517)
Cash and cash equivalents at beginning of year	$ 26,612	32,165	34,682
Cash and cash equivalents at end of period		$ 26,612	$ 32,165